DTC B27A8-13: Outside Luggage Compartment (Back Door) Electrical key Antenna Circuit Open [11/2021 - ]: Procedure
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2025 Lexus NX 350, 2025 Lexus NX 250, 2024 Lexus NX 350, 2024 Lexus NX 250, and 2023 Lexus NX 350. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK CONNECTOR CONNECTION
- Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and electrical key antenna (outside luggage compartment).
OK
Connectors are properly connected.
Result
Proceed to OK NG
Result:
NG
CONNECT CONNECTORS PROPERLY
Result:
OK
See step 2
- Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and electrical key antenna (outside luggage compartment).
- CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE COMPARTMENT))
- Disconnect the G12 certification ECU (smart key ECU assembly) connector.
- Disconnect the O15 electrical key antenna (outside luggage compartment) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition G12-4 (CLG8) - O15-2 (ANTE8) Always Below 1 Ω G12-3 (CG8B) - O15-1 (CLGB) Always Below 1 Ω - Reconnect the G12 certification ECU (smart key ECU assembly) connector.
Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 3
- CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE COMPARTMENT))
*a Component with harness connected
(Certification ECU (Smart Key ECU Assembly))*b Waveform 1 *c Waveform 2 - - - Using an oscilloscope, check the waveform.
OK
Tester Connection Condition Tool Setting Specified Condition G12-4 (CLG8) - D58-29 (E) Procedure: - Ignition switch off
- Electrical key transmitter sub-assembly brought outside vehicle
- All doors closed
- Back door opener switch assembly off → on
5 V/DIV., 50 ms./DIV. Pulse generation
(See waveform 1)G12-3 (CG8B) - D58-29 (E) Procedure: - Ignition switch off
- Electrical key transmitter sub-assembly brought outside vehicle
- All doors closed
- Back door opener switch assembly off → on
5 V/DIV., 50 ms./DIV. Pulse generation
(See waveform 2)Result
Proceed to OK NG
Result:
OK
REPLACE ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE COMPARTMENT). Refer to REMOVAL [11/2021 - ]
Result:
NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to REMOVAL [11/2021 - ]
- Using an oscilloscope, check the waveform.